Crossing-based interface

Where a pointing task involves moving a cursor inside a graphical object and pressing a button, a goal-crossing task involves moving a cursor beyond a boundary of a targeted graphical object to trigger an effect.

Goal crossing has been little investigated, despite sometimes being used on today's interfaces (e.g., mouse-over effects, hierarchical menus navigation, auto-retractable taskbars and hot corners).

Still, several advantages of crossing over pointing have been identified: There are several other ways of triggering actions in user interfaces, either graphic (gestures) and non-graphic (keyboard shortcuts, speech commands).

Variants of Fitts' law have been described for goal-crossing tasks (Accot and Zhai 2002).

The Law of crossing describes the allowed variability in the direction perpendicular to movement, and the steering law describes movement along a tunnel.

Fold n' Drop, a crossing-based interaction technique for dragging and dropping files between overlapping windows.